linux-stable.git/drivers/block, branch v5.6.8 Linux kernel stable tree loop: Better discard support for block devices 2020-04-29T14:34:32+00:00 Evan Green evgreen@chromium.org 2020-04-03T14:43:04+00:00 5ca31d1b4dfe63bad9b894f3c10fd17e665dcbf5 [ Upstream commit c52abf563049e787c1341cdf15c7dbe1bfbc951b ] If the backing device for a loop device is itself a block device, then mirror the "write zeroes" capabilities of the underlying block device into the loop device. Copy this capability into both max_write_zeroes_sectors and max_discard_sectors of the loop device. The reason for this is that REQ_OP_DISCARD on a loop device translates into blkdev_issue_zeroout(), rather than blkdev_issue_discard(). This presents a consistent interface for loop devices (that discarded data is zeroed), regardless of the backing device type of the loop device. There should be no behavior change for loop devices backed by regular files. This change fixes blktest block/003, and removes an extraneous error print in block/013 when testing on a loop device backed by a block device that does not support discard. Signed-off-by: Evan Green <evgreen@chromium.org> Reviewed-by: Gwendal Grignou <gwendal@chromium.org> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> [used updated version of Evan's comment in loop_config_discard()] [moved backingq to local scope, removed redundant braces] Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit c52abf563049e787c1341cdf15c7dbe1bfbc951b ]

If the backing device for a loop device is itself a block device,
then mirror the "write zeroes" capabilities of the underlying
block device into the loop device. Copy this capability into both
max_write_zeroes_sectors and max_discard_sectors of the loop device.

The reason for this is that REQ_OP_DISCARD on a loop device translates
into blkdev_issue_zeroout(), rather than blkdev_issue_discard(). This
presents a consistent interface for loop devices (that discarded data
is zeroed), regardless of the backing device type of the loop device.
There should be no behavior change for loop devices backed by regular
files.

This change fixes blktest block/003, and removes an extraneous
error print in block/013 when testing on a loop device backed
by a block device that does not support discard.

Signed-off-by: Evan Green <evgreen@chromium.org>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
[used updated version of Evan's comment in loop_config_discard()]
[moved backingq to local scope, removed redundant braces]
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
rbd: don't test rbd_dev->opts in rbd_dev_image_release() 2020-04-23T08:37:53+00:00 Ilya Dryomov idryomov@gmail.com 2020-03-16T16:16:28+00:00 8d2e626d898c6179c3d264ac3e6eb6e8fd2b232f commit b8776051529230f76e464d5ffc5d1cf8465576bf upstream. rbd_dev->opts is used to distinguish between the image that is being mapped and a parent. However, because we no longer establish watch for read-only mappings, this test is imprecise and results in unnecessary rbd_unregister_watch() calls. Make it consistent with need_watch in rbd_dev_image_probe(). Fixes: b9ef2b8858a0 ("rbd: don't establish watch for read-only mappings") Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Reviewed-by: Jason Dillaman <dillaman@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b8776051529230f76e464d5ffc5d1cf8465576bf upstream.

rbd_dev->opts is used to distinguish between the image that is being
mapped and a parent.  However, because we no longer establish watch for
read-only mappings, this test is imprecise and results in unnecessary
rbd_unregister_watch() calls.

Make it consistent with need_watch in rbd_dev_image_probe().

Fixes: b9ef2b8858a0 ("rbd: don't establish watch for read-only mappings")
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jason Dillaman <dillaman@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
rbd: call rbd_dev_unprobe() after unwatching and flushing notifies 2020-04-23T08:37:53+00:00 Ilya Dryomov idryomov@gmail.com 2020-03-16T14:52:54+00:00 a62bf759cfae86c5db2a38f5baf2270046c5a7d6 commit 952c48b0ed18919bff7528501e9a3fff8a24f8cd upstream. rbd_dev_unprobe() is supposed to undo most of rbd_dev_image_probe(), including rbd_dev_header_info(), which means that rbd_dev_header_info() isn't supposed to be called after rbd_dev_unprobe(). However, rbd_dev_image_release() calls rbd_dev_unprobe() before rbd_unregister_watch(). This is racy because a header update notify can sneak in: "rbd unmap" thread ceph-watch-notify worker rbd_dev_image_release() rbd_dev_unprobe() free and zero out header rbd_watch_cb() rbd_dev_refresh() rbd_dev_header_info() read in header The same goes for "rbd map" because rbd_dev_image_probe() calls rbd_dev_unprobe() on errors. In both cases this results in a memory leak. Fixes: fd22aef8b47c ("rbd: move rbd_unregister_watch() call into rbd_dev_image_release()") Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Reviewed-by: Jason Dillaman <dillaman@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 952c48b0ed18919bff7528501e9a3fff8a24f8cd upstream.

rbd_dev_unprobe() is supposed to undo most of rbd_dev_image_probe(),
including rbd_dev_header_info(), which means that rbd_dev_header_info()
isn't supposed to be called after rbd_dev_unprobe().

However, rbd_dev_image_release() calls rbd_dev_unprobe() before
rbd_unregister_watch().  This is racy because a header update notify
can sneak in:

  "rbd unmap" thread                   ceph-watch-notify worker

  rbd_dev_image_release()
    rbd_dev_unprobe()
      free and zero out header
                                       rbd_watch_cb()
                                         rbd_dev_refresh()
                                           rbd_dev_header_info()
                                             read in header

The same goes for "rbd map" because rbd_dev_image_probe() calls
rbd_dev_unprobe() on errors.  In both cases this results in a memory
leak.

Fixes: fd22aef8b47c ("rbd: move rbd_unregister_watch() call into rbd_dev_image_release()")
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jason Dillaman <dillaman@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
rbd: avoid a deadlock on header_rwsem when flushing notifies 2020-04-23T08:37:53+00:00 Ilya Dryomov idryomov@gmail.com 2020-03-13T10:20:51+00:00 c4ac5c5b98321d57f6446b6b564d88b5c89dc42b commit 0e4e1de5b63fa423b13593337a27fd2d2b0bcf77 upstream. rbd_unregister_watch() flushes notifies and therefore cannot be called under header_rwsem because a header update notify takes header_rwsem to synchronize with "rbd map". If mapping an image fails after the watch is established and a header update notify sneaks in, we deadlock when erroring out from rbd_dev_image_probe(). Move watch registration and unregistration out of the critical section. The only reason they were put there was to make header_rwsem management slightly more obvious. Fixes: 811c66887746 ("rbd: fix rbd map vs notify races") Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Reviewed-by: Jason Dillaman <dillaman@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 0e4e1de5b63fa423b13593337a27fd2d2b0bcf77 upstream.

rbd_unregister_watch() flushes notifies and therefore cannot be called
under header_rwsem because a header update notify takes header_rwsem to
synchronize with "rbd map".  If mapping an image fails after the watch
is established and a header update notify sneaks in, we deadlock when
erroring out from rbd_dev_image_probe().

Move watch registration and unregistration out of the critical section.
The only reason they were put there was to make header_rwsem management
slightly more obvious.

Fixes: 811c66887746 ("rbd: fix rbd map vs notify races")
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jason Dillaman <dillaman@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
xen/blkfront: fix memory allocation flags in blkfront_setup_indirect() 2020-04-17T14:13:46+00:00 Juergen Gross jgross@suse.com 2020-04-03T09:00:34+00:00 9c6e9d82f29ef16564b74d6c07e5cece00aa94e0 commit 3a169c0be75b59dd85d159493634870cdec6d3c4 upstream. Commit 1d5c76e664333 ("xen-blkfront: switch kcalloc to kvcalloc for large array allocation") didn't fix the issue it was meant to, as the flags for allocating the memory are GFP_NOIO, which will lead the memory allocation falling back to kmalloc(). So instead of GFP_NOIO use GFP_KERNEL and do all the memory allocation in blkfront_setup_indirect() in a memalloc_noio_{save,restore} section. Fixes: 1d5c76e664333 ("xen-blkfront: switch kcalloc to kvcalloc for large array allocation") Cc: stable@vger.kernel.org Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Acked-by: Roger Pau Monné <roger.pau@citrix.com> Link: https://lore.kernel.org/r/20200403090034.8753-1-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 3a169c0be75b59dd85d159493634870cdec6d3c4 upstream.

Commit 1d5c76e664333 ("xen-blkfront: switch kcalloc to kvcalloc for
large array allocation") didn't fix the issue it was meant to, as the
flags for allocating the memory are GFP_NOIO, which will lead the
memory allocation falling back to kmalloc().

So instead of GFP_NOIO use GFP_KERNEL and do all the memory allocation
in blkfront_setup_indirect() in a memalloc_noio_{save,restore} section.

Fixes: 1d5c76e664333 ("xen-blkfront: switch kcalloc to kvcalloc for large array allocation")
Cc: stable@vger.kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Link: https://lore.kernel.org/r/20200403090034.8753-1-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
null_blk: fix spurious IO errors after failed past-wp access 2020-04-17T14:13:18+00:00 Alexey Dobriyan adobriyan@gmail.com 2020-02-12T20:23:20+00:00 6dc42bc90669ef3d90e9321d3007f36662553a37 [ Upstream commit ff77042296d0a54535ddf74412c5ae92cb4ec76a ] Steps to reproduce: BLKRESETZONE zone 0 // force EIO pwrite(fd, buf, 4096, 4096); [issue more IO including zone ioctls] It will start failing randomly including IO to unrelated zones because of ->error "reuse". Trigger can be partition detection as well if test is not run immediately which is even more entertaining. The fix is of course to clear ->error where necessary. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alexey Dobriyan (SK hynix) <adobriyan@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit ff77042296d0a54535ddf74412c5ae92cb4ec76a ]

Steps to reproduce:

	BLKRESETZONE zone 0

	// force EIO
	pwrite(fd, buf, 4096, 4096);

	[issue more IO including zone ioctls]

It will start failing randomly including IO to unrelated zones because of
->error "reuse". Trigger can be partition detection as well if test is not
run immediately which is even more entertaining.

The fix is of course to clear ->error where necessary.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexey Dobriyan (SK hynix) <adobriyan@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
null_blk: Suppress an UBSAN complaint triggered when setting 'memory_backed' 2020-04-17T14:13:18+00:00 Bart Van Assche bvanassche@acm.org 2020-03-10T04:26:19+00:00 15dff7aa75469e2754d65f52dadb5ef3e78d441b [ Upstream commit b9853b4d6fb403ccb1d4d82e2d39fc17fc07519c ] Although it is not clear to me why UBSAN complains when 'memory_backed' is set, this patch suppresses the UBSAN complaint that is triggered when setting that configfs attribute. UBSAN: Undefined behaviour in drivers/block/null_blk_main.c:327:1 load of value 16 is not a valid value for type '_Bool' CPU: 2 PID: 8396 Comm: check Not tainted 5.6.0-rc1-dbg+ #14 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 Call Trace: dump_stack+0xa5/0xe6 ubsan_epilogue+0x9/0x26 __ubsan_handle_load_invalid_value+0x6d/0x76 nullb_device_memory_backed_store.cold+0x2c/0x38 [null_blk] configfs_write_file+0x1c4/0x250 [configfs] __vfs_write+0x4c/0x90 vfs_write+0x145/0x2c0 ksys_write+0xd7/0x180 __x64_sys_write+0x47/0x50 do_syscall_64+0x6f/0x2f0 entry_SYSCALL_64_after_hwframe+0x49/0xbe Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Cc: Johannes Thumshirn <jth@kernel.org> Cc: Hannes Reinecke <hare@suse.com> Cc: Ming Lei <ming.lei@redhat.com> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit b9853b4d6fb403ccb1d4d82e2d39fc17fc07519c ]

Although it is not clear to me why UBSAN complains when 'memory_backed'
is set, this patch suppresses the UBSAN complaint that is triggered when
setting that configfs attribute.

UBSAN: Undefined behaviour in drivers/block/null_blk_main.c:327:1
load of value 16 is not a valid value for type '_Bool'
CPU: 2 PID: 8396 Comm: check Not tainted 5.6.0-rc1-dbg+ #14
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Call Trace:
 dump_stack+0xa5/0xe6
 ubsan_epilogue+0x9/0x26
 __ubsan_handle_load_invalid_value+0x6d/0x76
 nullb_device_memory_backed_store.cold+0x2c/0x38 [null_blk]
 configfs_write_file+0x1c4/0x250 [configfs]
 __vfs_write+0x4c/0x90
 vfs_write+0x145/0x2c0
 ksys_write+0xd7/0x180
 __x64_sys_write+0x47/0x50
 do_syscall_64+0x6f/0x2f0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
null_blk: Handle null_add_dev() failures properly 2020-04-17T14:13:18+00:00 Bart Van Assche bvanassche@acm.org 2020-03-10T04:26:22+00:00 9fbcc855fab3d7b2809ed1b4f35212c7b57661ae [ Upstream commit 9b03b713082a31a5b90e0a893c72aa620e255c26 ] If null_add_dev() fails then null_del_dev() is called with a NULL argument. Make null_del_dev() handle this scenario correctly. This patch fixes the following KASAN complaint: null-ptr-deref in null_del_dev+0x28/0x280 [null_blk] Read of size 8 at addr 0000000000000000 by task find/1062 Call Trace: dump_stack+0xa5/0xe6 __kasan_report.cold+0x65/0x99 kasan_report+0x16/0x20 __asan_load8+0x58/0x90 null_del_dev+0x28/0x280 [null_blk] nullb_group_drop_item+0x7e/0xa0 [null_blk] client_drop_item+0x53/0x80 [configfs] configfs_rmdir+0x395/0x4e0 [configfs] vfs_rmdir+0xb6/0x220 do_rmdir+0x238/0x2c0 __x64_sys_unlinkat+0x75/0x90 do_syscall_64+0x6f/0x2f0 entry_SYSCALL_64_after_hwframe+0x49/0xbe Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Cc: Johannes Thumshirn <jth@kernel.org> Cc: Hannes Reinecke <hare@suse.com> Cc: Ming Lei <ming.lei@redhat.com> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 9b03b713082a31a5b90e0a893c72aa620e255c26 ]

If null_add_dev() fails then null_del_dev() is called with a NULL argument.
Make null_del_dev() handle this scenario correctly. This patch fixes the
following KASAN complaint:

null-ptr-deref in null_del_dev+0x28/0x280 [null_blk]
Read of size 8 at addr 0000000000000000 by task find/1062

Call Trace:
 dump_stack+0xa5/0xe6
 __kasan_report.cold+0x65/0x99
 kasan_report+0x16/0x20
 __asan_load8+0x58/0x90
 null_del_dev+0x28/0x280 [null_blk]
 nullb_group_drop_item+0x7e/0xa0 [null_blk]
 client_drop_item+0x53/0x80 [configfs]
 configfs_rmdir+0x395/0x4e0 [configfs]
 vfs_rmdir+0xb6/0x220
 do_rmdir+0x238/0x2c0
 __x64_sys_unlinkat+0x75/0x90
 do_syscall_64+0x6f/0x2f0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
null_blk: Fix the null_add_dev() error path 2020-04-17T14:13:17+00:00 Bart Van Assche bvanassche@acm.org 2020-03-10T04:26:21+00:00 f720d394829b2f1b0b08c2920d62d307f1ec6b31 [ Upstream commit 2004bfdef945fe55196db6b9cdf321fbc75bb0de ] If null_add_dev() fails, clear dev->nullb. This patch fixes the following KASAN complaint: BUG: KASAN: use-after-free in nullb_device_submit_queues_store+0xcf/0x160 [null_blk] Read of size 8 at addr ffff88803280fc30 by task check/8409 Call Trace: dump_stack+0xa5/0xe6 print_address_description.constprop.0+0x26/0x260 __kasan_report.cold+0x7b/0x99 kasan_report+0x16/0x20 __asan_load8+0x58/0x90 nullb_device_submit_queues_store+0xcf/0x160 [null_blk] configfs_write_file+0x1c4/0x250 [configfs] __vfs_write+0x4c/0x90 vfs_write+0x145/0x2c0 ksys_write+0xd7/0x180 __x64_sys_write+0x47/0x50 do_syscall_64+0x6f/0x2f0 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7ff370926317 Code: 64 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24 RSP: 002b:00007fff2dd2da48 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007ff370926317 RDX: 0000000000000002 RSI: 0000559437ef23f0 RDI: 0000000000000001 RBP: 0000559437ef23f0 R08: 000000000000000a R09: 0000000000000001 R10: 0000559436703471 R11: 0000000000000246 R12: 0000000000000002 R13: 00007ff370a006a0 R14: 00007ff370a014a0 R15: 00007ff370a008a0 Allocated by task 8409: save_stack+0x23/0x90 __kasan_kmalloc.constprop.0+0xcf/0xe0 kasan_kmalloc+0xd/0x10 kmem_cache_alloc_node_trace+0x129/0x4c0 null_add_dev+0x24a/0xe90 [null_blk] nullb_device_power_store+0x1b6/0x270 [null_blk] configfs_write_file+0x1c4/0x250 [configfs] __vfs_write+0x4c/0x90 vfs_write+0x145/0x2c0 ksys_write+0xd7/0x180 __x64_sys_write+0x47/0x50 do_syscall_64+0x6f/0x2f0 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 8409: save_stack+0x23/0x90 __kasan_slab_free+0x112/0x160 kasan_slab_free+0x12/0x20 kfree+0xdf/0x250 null_add_dev+0xaf3/0xe90 [null_blk] nullb_device_power_store+0x1b6/0x270 [null_blk] configfs_write_file+0x1c4/0x250 [configfs] __vfs_write+0x4c/0x90 vfs_write+0x145/0x2c0 ksys_write+0xd7/0x180 __x64_sys_write+0x47/0x50 do_syscall_64+0x6f/0x2f0 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: 2984c8684f96 ("nullb: factor disk parameters") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Cc: Johannes Thumshirn <jth@kernel.org> Cc: Hannes Reinecke <hare@suse.com> Cc: Ming Lei <ming.lei@redhat.com> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 2004bfdef945fe55196db6b9cdf321fbc75bb0de ]

If null_add_dev() fails, clear dev->nullb.

This patch fixes the following KASAN complaint:

BUG: KASAN: use-after-free in nullb_device_submit_queues_store+0xcf/0x160 [null_blk]
Read of size 8 at addr ffff88803280fc30 by task check/8409

Call Trace:
 dump_stack+0xa5/0xe6
 print_address_description.constprop.0+0x26/0x260
 __kasan_report.cold+0x7b/0x99
 kasan_report+0x16/0x20
 __asan_load8+0x58/0x90
 nullb_device_submit_queues_store+0xcf/0x160 [null_blk]
 configfs_write_file+0x1c4/0x250 [configfs]
 __vfs_write+0x4c/0x90
 vfs_write+0x145/0x2c0
 ksys_write+0xd7/0x180
 __x64_sys_write+0x47/0x50
 do_syscall_64+0x6f/0x2f0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7ff370926317
Code: 64 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
RSP: 002b:00007fff2dd2da48 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007ff370926317
RDX: 0000000000000002 RSI: 0000559437ef23f0 RDI: 0000000000000001
RBP: 0000559437ef23f0 R08: 000000000000000a R09: 0000000000000001
R10: 0000559436703471 R11: 0000000000000246 R12: 0000000000000002
R13: 00007ff370a006a0 R14: 00007ff370a014a0 R15: 00007ff370a008a0

Allocated by task 8409:
 save_stack+0x23/0x90
 __kasan_kmalloc.constprop.0+0xcf/0xe0
 kasan_kmalloc+0xd/0x10
 kmem_cache_alloc_node_trace+0x129/0x4c0
 null_add_dev+0x24a/0xe90 [null_blk]
 nullb_device_power_store+0x1b6/0x270 [null_blk]
 configfs_write_file+0x1c4/0x250 [configfs]
 __vfs_write+0x4c/0x90
 vfs_write+0x145/0x2c0
 ksys_write+0xd7/0x180
 __x64_sys_write+0x47/0x50
 do_syscall_64+0x6f/0x2f0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 8409:
 save_stack+0x23/0x90
 __kasan_slab_free+0x112/0x160
 kasan_slab_free+0x12/0x20
 kfree+0xdf/0x250
 null_add_dev+0xaf3/0xe90 [null_blk]
 nullb_device_power_store+0x1b6/0x270 [null_blk]
 configfs_write_file+0x1c4/0x250 [configfs]
 __vfs_write+0x4c/0x90
 vfs_write+0x145/0x2c0
 ksys_write+0xd7/0x180
 __x64_sys_write+0x47/0x50
 do_syscall_64+0x6f/0x2f0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: 2984c8684f96 ("nullb: factor disk parameters")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost 2020-03-09T23:02:32+00:00 Linus Torvalds torvalds@linux-foundation.org 2020-03-09T23:02:32+00:00 7de41b120bb7fbe83bb46e7585c7346d21b93585 Pull virtio fixes from Michael Tsirkin: "Some bug fixes all over the place" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: virtio_balloon: Adjust label in virtballoon_probe virtio-blk: improve virtqueue error to BLK_STS virtio-blk: fix hw_queue stopped on arbitrary error virtio_ring: Fix mem leak with vring_new_virtqueue() 
Pull virtio fixes from Michael Tsirkin:
 "Some bug fixes all over the place"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio_balloon: Adjust label in virtballoon_probe
  virtio-blk: improve virtqueue error to BLK_STS
  virtio-blk: fix hw_queue stopped on arbitrary error
  virtio_ring: Fix mem leak with vring_new_virtqueue()